Electrical connector



Mardi 26, 1963 w. R. scHELLER 3,083,345

ELECTRICAL CONNECTOR Filed NOV. 21.*1960 Z5 Sheets-Sheet 1 a \T, ea Pf3:l warnen R. SCHELLER Nif-5R "6 l CIMA, HM' 407%# March 25, 1963 w. R.scHELLER 3,083,345

ELECTRICAL coNNEcToR Filed Nov. 21. 19Go s sheets-sheet 2 INVENTOR.LJILFRED R. SCHELLER Cyn/) Mmm) rjalw/ W. R- SCHELLER ELECTRICALCONNECTOR March 26, 1963 3 Sheets-Sheet 5 Filed NOV. 21, 1960 INVENTQRUmano R. cmaLLeR United States Patent O 3,083,345 ELECTRICAL CUNNECTURWilfred R. Scheller, New Cumberland, Pa., assignor to AMF Incorporated,Harrisburg, Pa. Fiied Nov. 21, 1969, Ser. No. 70,533 6 Claims. (Cl.339-47) This invention relates to electrical connectors of the typeadapted to form disengageable electrical connections between conductors.

An object of the invention is to provide an improved disengageableelectrical connecting means. A further object is to provide anelectrical connector which is engageable with a duplicate connector toform a disengageable electrical connection. A still further object is toprovide an electrical connector which is engageable with a duplicateconnector to form a connection which does not require an extraneousholding means such as a dielectric block. A still further object is toprovide a disengageable electrical connection comprising individualelectrical connectors which can be made from relatively thin stock metaland in relatively small sizes without sacrifice of electrical ormechanical integrity. A still further object is to provide disengageableelectrical connectors which are mechanically foolproof in the sense thatthey cannot be mated with each other or with other mating electricalconnector parts excepting in the proper and intended manner.

These and other objects of the invention are achieved in an electricalconnector of generally channel-shaped cross section having an enclosedelongated slot in each of the sidewalls of the channel. Thelongitudinallyextending portions of the sidewalls adjacent to theseslots function as springs which are integral at each end with thechannel sidewalls and which, upon insertion of a mating connector part,establish electrical contact therewith. The provision of springs of thistype, which are integral at each end with the connector itself, assuresthe development of the required contact pressure for -a high qualityconnection and the connectors can, furthermore, be formed of relativelythin stock material. Connectors in accordance with the invention cantake alternative forms; for example, the Contact springs in the channelsidewalls can be formed `adjacent the longitudinal edges of thesesidewalls and the width of the connector can be made such that twoconnectors can be stacked or nested with their axes in parallelrelationship. In this embodiment, the longitudinally extending contactsprings of the one connector then grip the base of the channel-shapedcross section of the other connector. In `another embodiment of theinvention, the contact springs are formed in the channel sidewalls at alocation intermediate between the sidewall edges and the web of thechannel, and the spacing between these opposed faces of the springs ismade such that two duplicate connectors can be mated with each other by`aligning them in inverted, parallel and offset relationship and movingthem relatively together so that the sidewall of each connector isgripped between tlie contact springs of the other connector. Thisembodiment has the advantage of providing two mechanically separate butelectrically common Zones of contact.

Both embodiments permit the -attainment of adequate contact pressuresfor a high quality connection with rela-A tively thin stock material andwith connectors formed in relatively small sizes. The principles of theinvention are thus highly advantageous in connection with the formationof disengageable electrical connections between relatively small wires,i.e, AWG 14-26. Connectors in accordance with the invention can, asmentioned above, be mated with duplicate connectors and this isgenerally reckoned as an advantageous feature since it reduces the icenumber of parts which must be utilized to form disengageableconnections. An added feature is, however, that the embodiments of theinvention disclosed herein can also be mated with simple terminaldevices, such as tabs, Which `are commonly used in the manufacture ofelectrical devices having wires which must be connected to the wires inother devices at a place and time remote from the time and place ofmanufacture.

In the drawing:

FIGURE 1 is a perspective view of an electrical connector in accordancewith the invention.

FIGURE 2 is a side View and FIGURE 3 is a top plan View of theembodiment `of FIGURE l.

FIGURE 4 is a sectional view taken along the lines 4 4 of FIGURE 2.

FIGURE 5 is a plan view of the punched-out blank from which theconnector of FIGURE 1 is formed.

FIGURE 6 is a longitudinal sectional View taken along lines 66 of FIGURE9` showing a pair of dielectric blocks having aligned cavities thereinintended for reception of connectors of the type shown in FIGURE 1.

FIGURE 7 is a View taken along the lines 7-7 of FIGURE 6.

FIGURE 8 is a view taken along the lines 8 8` of FIGURE 6.

FIGURE 9' is a View taken along the lines 9-9 of FIGURE 6'and showingthe rear or back surface of one of the dielectric blocks.

FIGURE l() is a perspective View showing the form of the cavity intendedfor the connector of FIGURE 1.

FIGURE 11 is a view similar to FIGURE 6 but showing connectors in thedielectric blocks and in mated relationship with each other.

FIGURE 12 is a View taken along the lines 12-12 of FIGURE 11.

FIGURE 13 is a perspective view of an alternative embodiment of theinvention.

FIGURE 14 is a top plan view of the connector of FIGURE 13.

FIGURE 15 is a plan View of the blank from which the connector of FIGURE13 is formed.

FIGURE 16 is an end View of the connector of FIG- URE 13.

FIGURE 17 is a View taken along the lines 17-17 of FIGURE 14.

FIGURE 18 is a perspective view showing a pair of connector blockshaving connectors in accordance with FIGURE 13 disposed therein.

FIGURE 19 is a side View with parts broken away showing the dielectricblocks of FIGURE 18 in their assembled relationship to a panel.

FIGURE 20 is a view taken along the lines Zt-Ztl of FIGURE 19.

FIGURE 21 is a view taken along the lines 21-21 of FIGURE 19 but showingmated connectors in only one of the cavities in the blocks; and

FIGURE 22 is a perspective lines 22-22 of FIGURE 21.

Referring now to FIGURES 1-5 of the drawing, in accordance with oneembodiment of the invention the connector has a contact portiongenerally indicated at 2 and a crimp portion 4. The crimp portioncomprises a wire crimp 8, which secures the connector to the conductingcore of a wire, and an insulation crimp Il) which secures the connectorto the insulating sheath of a wire 12. In the disclosed embodiment thecontact portion and the crimp portion are in axial alignment with eachother, however, if desired the Contact portion can extend obliquely ortransversely of the crimp portion to meet specialized requirements. Itis also feasible to secure the connector onto the wire end byalternative forms of crimps or in some manner other than crimping.

View taken along the The crimp portion 4 is joined to the contactportion by means of a generally divergent channel-shaped transl` tionsection 6. This transition section merges with a rear channel section ofthe contact portion having a web 14 and a pair of upstanding sidewalls16. Ears 1S, which extend outwardly of the planes of the sidewalls, areprovided to lock the connector within a dielectric block in a mannerdescribed below.

The frontal portion of the Contact comprises a web 2@ having upstandingsidewalls 22 which are substantially coplanar with the sidewalls 16.This frontal channel section 20, 22 and the channel section 14, le areconnected by means of axially extending elements 24, 34 which functionas contact springs. The central portions 24 of these springs aredisplaced inWardy towards the connector axis and function as contactportions of the spring. The longitudinal edges of the sidewalls 16, 22which are remote from the webs 14, 20 are also connected to each otherby means of axially extending elements 28. These elements are displacedinwardly with respect to the webs, as shown best in FIGURE 4, and theirlongitudinal edges 30 are reversely bent outwardly to provide a doublethickness of metal along these edges. The bent-over edges extendrearwardly of the contact and towards the crimp, as shown at 32, anddivergently with Arespect to the contact axis to provide an additionalmeans for locking the connector in a dielectric block as is alsodescribed below.

The connector of FIGURE l is advantageously formed from strip metal byprogressive die forming operations.

. FIGURE shows one form of blank which has been stamped from strip metaland which is subsequently bent and formed to produce the connector ofFlGURE l. The various portions of this blank are identified by the samereference numerals, dilferentiated by means of prime marks, as thoseused in the foregoing description of the formed connector of FIGUREV 1.Itwill be noted that .the two webs 14, 20 are Vformed by stamping out arectangular opening 26 in the blank and that the contact springs 24, 34are formed by stamping slots 36 in the blank on each side of the centralopening. Connectors of this type are advantageously manufactured instrip form with each connector being integral with the next adjacentconnector so that they can be appliedrto'wire ends by means of crimpingpresses having strip feeding means'.

Two connectors of the type shown in FIGURE l can inverted relationshipwithV each other and moving them relatively together until eachconnector has one `of its longitudinal edges clamped between the contactsprings of the other connector as shown in FIGURE l2. In order toachieve this arrangement, the spacing between the opposed faces of thecontact spring portions 24 is made slightly less than the spacingbetween the external surfaces of the folded-over portions 30 and theinternal surfaces 28 of the corresponding longitudinal edges so that theedges 36 will be resiliently gripped between the springs. An addeddimensional limitation is that the spacing between the internal surfaceof each ofthe contact portions 24 and the surface of its respectiveVsidewall 4be mated with each other by aligning them in offset and plane,as deiined by the sidewalls 16, 22 is made less.

providing aligned but offset'cavities for reception of the connectors.The block 38 has a frontal wall 42. and a rear wall 44. The cavityextends inwardly from this rear wall and has lirst a generallyrectangular enlarged por-k 'tion 46 which is intended to receive theinsulation Crimp.

This enlarged portion merges, by means ofk a truncated pyramidal section48, with a central cavity section 50 of somewhat reduced cross section.This central section 50 has a centrally located barrier 52 extendingpartially extent.

therethrough on one of its walls. The adjoining walls are provided withslots 54 which terminate at rearwardly facing shoulders 56. Therighthand portion of the cavity in the block 38 is enlarged by an odsetopening which extends inwardly from surface 42 and which has walls 62,64 (FIGURE 8) which are parallel to the walls of the central section 50.A pair of grooves 58 extend from this oiset opening into the sidewallsof the central section 50` on each side of barrier 52 and between thegrooves 54 and the base of the cavity (as viewed in FiGURES 6 and 8).These grooves terminate in shoulders 60 which face the frontal Wall 42,

lock 33 is adapted to receive a terminal of the type shown in FIGURE l-by axial insertion thereof through the enlarged entrance d6 of the rearwall. Upon such insertion, the ears 13 will move relatively into thegrooves 54 until they come to rest against the shoulders 56, and thedivergent retaining springs 32 will be compressed by the sidewalls ofthe opening until they snap outwardly and into the grooves 58 so thatthe terminal is locked within the cavity. The Contact portion of theterminal will then reside within the righ-thand portion of the openingand will be adjacent to the enlarged portion of the opening which isdefined -by the walls 62, 64. A properly inserted terminal cannot -bewithdrawn by virtue of the engagement of the retainer springs 32 withthe shoulders 6i? Iand it cannot move further rightwardly into theopening byvirtue of the engagement of the ears 18 with the shoulders Se.The block di) is in most respects similar to the `block 38 but is not asthick as block 38 .and does not have an enlarged cavity sectioncorresponding to the enlarged section 62, 64. The thickness of block d0is such that the contact portion of an inserted terminal extends beyondthe front wall 65. The details of the cavity of block 4@ are identifiedby the same reference numerals `'as those used in the description of theblock 38 with the letter a used to differentiate the two parts. Sincethe -two blocks Iare substantially the same, the block 33 need not bedescribed in further detail. It will be apparent from FIGURES 6 and 7that in use, the cavity in block 40 is inverted and offset with respectto the cavity of the block 38. This relationship of 4the cavitiespermits accommodation of the terminals, as shown in FIGURE l2.

The embodiment of FIGURE l possesses several specific `advantages inaddition to the advantages of the generic concept of the invention.Referring to FIGURE l2, it will be seen that since the contact springs24 of each connector engage the other connector, two mechanicallyseparate bu-t electrically common zones of contact Iare provided betweenthe two connectors. Thus, if one of the connectors should have avdefective contact portion, there remains a second set of contact 4areasto carry out the intended electrical function of the device. Anotherdistinct advantage is that the electrical contact between thelongitudinal edges lof the connector and the Vcontact springs isVenhanced by virtue of the folded-over portions 30 of the edges. Whenthese edges are folded, any spring back tendency which remains will tendto cause the folded-over portions to move outwardly to a slight Thus,when the two connectors Iare engaged with each other, these edgeportions, if they tend to move at all by virtue of theirinherent`resiliency will tend to move toward the contact surface of the matingconnector.

While VconnectorsV of the type shownV in FIGURE 1 are usually used inblocks .of 4the types shownin FIG- .URES 6-10, it is also entirelypractical to provide a much `simpler/form of block, for example, asimple tubular member of suitable dielectric material, land to relyentirely upon Vthe connectors themselves to maintain their engagementwith each other. Alternatively, if it is not A`essential that theconnection formed with the connectors of FGURE l be insulated, theconnectors can be engaged with eachother without the benefit of asurrounding dielectric block and, after engagement, they will remain inmated relationship by virtue of their interlocked relationship asillustrated in FIGURE 12.

Referring now to FIGURES 13-17, 1an l.alternative form of the inventionprovides a contact portion 70 and a crimp portion 72. Again, the crimpportion comprises a wire crimp 74 and an insulation crimp 76 to permitat- :tachment to the conducting core and vthe insulation respectively ofa conductor 78.

The contact portion is again of generally channelshaped or U-shapedcross section. This contact portion comprises a web 80 having upstandingsidewalls which, in their portions 82 immediately adjacent to the web,are substantially parallel to each other and extend normally of theplane of the web. Enclosed slots 8'4 extend axially in these sidewallssubstantially midway between the web and the longitudinal edges of thesidewalls. At each end of the contact portion and on each side of 4theslots, the sidewalls 86, 88 diverge. The remaining longitudinal edgeportions 90, 92 of the channel function -as contact springs, the centralportions 92 of these edges being inwardly displaced. The spacing betweenthe opposed faces of the contact portions 92 is normally substantiallyequal to or slightly less than the width of the sidewall portions 82 asshown in FIGURE 17.

The edge por-tions of the channel extend rearwardly toward the conductor78 and are bent inwardly to form ears 96 overlying the web of thechannel to retain the connector in a block in a manner described below.The web also provides Ia struck up rearwardly facing tang 98 for thissame purpose. The frontal ends of the sidewalls are advantageouslydivergent with respect to the axis of the channel as shown at 100 tofacilitate engagement of a connector of this type with a duplicateyconnector in the manner described below.

The embodiment of FIGURE 13 is again advantageously formed from stripmetal by stamping and forming by progressive die forming operations.FIGURE 15 shows a blank from which the connector of FIGURE 13 is formed,the various parts of this blank being identified yby the same referencenumerals as those used in FIGURE 13 but differentiated by means of primemarks.

In use, a connector of the type shown in FIGURE 13 can be mated with aduplicate connector -by aligning the two connectors in offsetrelationship, one on top of the other, and moving them relativelytogether until the lower portions of the sidewall of the upper connectorare gripped between the contact springs of the lower connector. Again,the contact springs which establish the electrical contact between thetwo connectors are integral at each end with the sidewalls of thechannel so that relatively low yield strength materials can be employedin the practice of the invention. It is also apparent that the form ofthe connector of FIGURE 13 is extremely simple and is easily formed andshaped by means of relatively simple and straightforward die formingoperation.

FIGURES 18-22 illustrate a pair of connector blocks adapted to receiveterminals of the type shown in FIG- URE 13. As shown in FIGURE Z1, thecavities in the blocks are relatively wider in their upper portions (asviewed in the drawing) than in their lower portions in order toaccommodate the enlarged upper portions of the connectors. The cavitieshave an enlarged entrance portion 114 which merges with a centralsection 116 of somewhat smaller cross section. A block 120 projects intothiscentral section and has an inclined face 122 and a pair of grooves124 which face the rear wall of the terminal. The portion of the cavitywhich is adjacent to the front wall is enlarged as shown at 1118, inorder to .accommodate the nested contact portions of a pair of matedconnectors as shown in FIGURE 19.

As with the previously described embodiment, the connector can beinserted into the cavities of the block only in the proper and intendedmanner. Thus, the connector must be aligned with the open side of itschannel facing the enlarged side of the opening prior .to insertion.Upon insertion, the tang 98 is depressed until it passes the dependingblock 120 at which time it returns to its normal position and lodgesagainst the shoulder 126 thereby to prevent withdrawal of the terminalfrom the connector block. The inwardly directed ears 96 enter thegrooves 124 and abut the shoulders at the ends of .these grooves therebyto prevent insertion of the connector into the block beyond the desiredpoint. The mating connector block 102 is in many respects similar to theblock 104 but is relatively shorter `since the contact portions of theconnectors mounted in block 102 must project beyond the face of theblock so that they can enter the cavities of the block 104. Thestructural features of the block 102 and particularly of the cavities of.this block which are similar to, and correspond to, the features of theblock and cavities 104 are identified by the same reference numeralsdifferentiated by the letter A.

The blocks 102, 104 may be provided with suitable means Ito secure themto a panel. As shown in FIGURE l18, the block 104 may be provided with apair of wings or larms 106 having hooked ends on two of its sides and onits remaining sides it may be provided with flexible bracing means 108.With this arrangement, when it is desired to mount the block 104 on apanel, the block is tilted relative to the plane of the panel until oneof the arms 106 can be inserted through( the panel opening. The blockcan then bemanipulated to position the remaining arm on the oppositeside of the panel so that the hooked ends of the arms will preventwithdrawal of the block from the opening in the panel and will functionto x the block with respect to the panel. Mounting arrangements of this'type are shown and described in the United States patent to Swengel No.2,891,103.

It is also advantageous to provide a shroud 128 on the block i102 toprotect the protruding contact portions of the terminals mounted in`this block. The preferred form of the block shown in the drawing willbe noted to provide accommodation for nine pairs of terminals with theterminals arranged in three parallel rows. For closest possible spacing,the center row of terminals is staggered with respect to the outer rowsas shown in IFIGURE d8.

The embodiment of the invention shown in FIGURE 13 and the embodiment ofyFIGURE l both provide the Isalient advantage of a contact spring whichis formed from the same metal as the terminal itself and which isintegral at each end with the body of the terminal. This arrangement hasthe primary advantage of permitting the attainment of virtually anydesired contact pressure even if the terminals themselves are formed ofrelatively lthin material and are formed from a metal having acomparatively low yield point. Heretofore, the attainment of adequatecontact pressures and the construction of contact springs indisengageable type electrical connectors has frequently engendered theuse of relatively thick gauge stock material and has required the use ofmaterial having a relatively high yield point in order to achieve therequired spring characteristics. Thus, it is common to use fullyhardened brass strip for the manufacture of some types of disengageableconnectors in order that the spring which is formed as part of theconnector will have adequate strength and will have the required springproperties. By way of contrast, it has been found that connectors inaccordance with the instant invention can be manufactured from extremelythin stock and that the contact springs will still be adequately strongand durable to accomplish their intended function. This is a result o-fthe fact that the springs are in reality relatively short beams whichare integral at each end with the connector contact portion itself.Beams of this type can be loaded to a fairly high level Without theimposition of unduly high unit stresses and, therefore, withoutexceeding the yield strength of the material.

Changes in construction will occur to those skilled in the art andvarious apparently different modifications epesses and embodiments maybe made `without departing from the scope of the invention. The matterset forth in the foregoing description and accompanying drawings isoffered by Away of illustration only. The actual scope of the inventionis intended to be defined in the following claims when viewed in theirproper perspective against the prior art.

I claim: Y

1. An electrical connector comprising a contact portion of generallyU-shaped cross-section, means integral with one end of said U-shapedcontact portion forV securing said connector to a conductor, theupstanding sidewalls of said U-shaped contact portion each having anenclosed axially extending slot therein thereby to form an axiallyextending element which is integral at each end with its sidewall, saidaxially extending elements being displaced relatively towards eachother, with respect to the planes of their sidewalls, the spacingbetween the opposed faces of said axially extending elements beingslightly less than the thickness of the longitudinal marginal portionsof said sidewalls of said U-shaped contact portion, and the spacingbetween the inner -surface of each axially extending element and theouter surface of its respective sidewall being less than the spacingbetween the opposed surfaces of said longitudinal marginal portions ofsaid sidewalls thereby to permit mating of said connector with aduplicate connector which is in inverted, parallel offset relationship,said longitudinally extending elements functioning as springs to holdthe longitudinal marginal portions of one of the sidewalls of saidduplicate connector.

2. A connector as set forth in claim 1 in which said longitudinalmarginal portions of said sidewalls are reversely bent thereby toprovide a double thickness of metal for reception between thelongitudinally extending elements of said duplicate connector.

' 3. A connector as set forth in claim 2 in which said sidewalls haveoutwardly directed ears thereon and in which said marginal portions havedivergent retaining springs extending rearwardly of said connector, saidears and said retaining springs being adapted to retain said connectorin a connector biocl:`

4. An electrical connector having a contact portion` distance such thatthe opposed inner surfaces of said inwardly displaced sections areseparated by a distance slightly less than the distance separating theexternal surfaces of said sidewalls which are adjacent to said webwhereby, said connector is adapted to receive the web and adjacentsidewall portions of a duplicate connector between said inwardlydisplaced sections.

5. An electrical connector having a contact portion comprising a webwith sidewalls extending therefrom on each longitudinal side, saidsidewalls comprising proximate and remote portions with respect to saidweb, said remote portions being outwardly offset at each end of saidcontact portion, each of said sidewalls having a longitudinallyextending slot therein between said remote connector is adapted toreceive the web and proximate sidewall portions of'a duplicate connectorbetween said inwardly displaced remote sidewall portions.

6. An electrical connector having a contact portion comprising a webwith sidewalls extending therefrom on each longitudinal side, saidsidewalls comprising proximate and remote portions with respect to saidweb, said remote portions being outwardly offset at each end of saidcontact portion and having inwardly displaced intermediate sections, theopposed surfaces of said intermediate sections being spaced apart by adistance slightly less than the distance separating the externalsurfaces of said proximate portions whereby, said connector is adaptedto receive the web and proximate sidewall portions of a duplicateconnector between said inwardly displaced sections, each of saidsidewalls having an inwardly extending ear at its end thereof which isopposite from its open end, said ears functioning as stops for retainingsaid connector' in a connector block.

References Cited in the file of this patent UNITED STATES PATENTS2,701,350 'Soreng Feb. l, 1955 2,711,524 Beaver June 21, 1955 .2,741,750Barre Y.. Apr. 10, 1956 V2,762,626 p, Knohl ..'Sept. 4, 1956 V2,785,387Batcheller Mar. 12, 1957 2,791,755 Hammell May 7, 1957

1. AN ELECTRICAL CONNECTOR COMPRISING A CONTACT PORTION OF GENERALLYU-SHAPED CROSS-SECTION, MEANS INTEGRAL WITH ONE END OF SAID U-SHAPEDCONTACT PORTION FOR SECURING SAID CONNECTOR TO A CONDUCTOR, THEUPSTANDING SIDEWALLS OF SAID U-SHAPED CONTACT PORTION EACH HAVING ANENCLOSED AXIALLY EXTENDING SLOT THEREIN THEREBY TO FORM AN AXIALLYEXTENDING ELEMENT WHICH IS INTEGRAL AT EACH END WITH ITS SIDEWALL, SAIDAXIALLY EXTENDING ELEMENTS BEING DISPLACED RELATIVELY TOWARDS EACHOTHER, WITH RESPECT TO THE PLANES OF THEIR SIDEWALLS, THE SPACINGBETWEEN THE OPPOSED FACES OF SAID AXIALLY EXTENDING ELEMENTS BEINGSLIGHTLY LESS THAN THE THICKNESS OF THE LONGITUDINAL MARGINAL PORTIONSOF SAID SIDEWALLS OF SAID U-SHAPED CONTACT PORTION, AND THE SPACINGBETWEEN THE INNER SURFACE OF EACH AXIALLY EXTENDING ELEMENT AND THEOUTER SURFACE OF ITS RESPECTIVE SIDEWALL BEING LESS THAN THE SPACINGBETWEEN THE OPPOSED SURFACES OF SAID LONGITUDINAL MARGINAL PORTIONS OFSAID SIDEWALLS THEREBY TO PERMIT MATING OF SAID CONNECTOR WITH ADUPLICATE CONNECTOR WHICH IS IN INVERTED, PARALLEL OFFSET RELATIONSHIP,SAID LONGITUDINALLY EXTENDING ELEMENTS FUNCTIONING AS SPRINGS TO HOLDTHE LONGITUDINAL MARGINAL PORTIONS OF ONE OF THE SIDEWALLS OF SAIDDUPLICATE CONNECTOR.